Red rice is considered the major weed in rice areas. The similarity between red rice and cultivated rice difficults the red rice control. Seed dormancy and viability in the soil allow the maintanence of the biotype in the area and facilite the dissemination in surrounded areas. Dormancy duration and intensity depend on biotype and environmental conditions during seed development. In general, biotypes have two types of dormancy: one from surrounding structures and the other one from embryo. The dormancy relief can occur on different times. It depends on environmental conditions (temperature and humidity) in afterripening. Some substances have shown good results on breaking dormancy, in special, acids and cytokinins, however, other hormones have shown only a partial effect. These substances have not affected the surrounding structures. The red rice’s mechanism of dormancy/relief is far from being stabilished.
germination; Oryza sativa; dormancy; plant hormones; physical barriers
